About how many tornadoes happen in an average year in the US? 1. 800
2.700
3.200
4.500

Casts and mold are a type of preservation where the original material decays, leaving a mold in surrounding rock that can be filled with another sediment a. true b. false

What two factors does carrying capacity compare? population size and resource use population growth and resource availability resource use and time population size and time

Ascientist is investigating the effects of salinity on fish development. he places fertilized fish eggs in an aquarium that contains low salinity and observes their development. what factor would improve experimental design the most? place the fish eggs in the open ocean because that is the natural habitat include another aquarium that has normal salinity to compare to the low salinity aquarium include an aquarium that replaces salt with sugar to confirm that the effects are specific to salt grow algae with the fish eggs in order to provide adequate nutrients to the developing embryos